This taxon, which has been included within Nymphaea odorata by some recent workers, was formerly almost universally accepted as a distinct species. In the southern parts of the range of subsp. tuberosa , where subsp. odorata is absent, subsp. tuberosa is easily distinguished morphologically from subsp. odorata . Farther north, where their ranges overlap, the distinctions break down in some populations but are maintained in others. Some western populations are probably the result of introductions. A pink-flowered form seen in southeastern Ohio appears to be derived from this subspecies.